title: Cks1 enhances transcription efficiency at the GAL1 locus by linking the Paf1 complex to the 19S proteasome.
abstract: Cks1 was originally identified based on genetic interactions with CDC28, the gene that encodes Cdk1 in the budding yeast Saccharomyces cerevisiae. Subsequent work has shown that Cks1 binds Cdc28 and modulates its activity against certain substrates. However, the Cks1/Cdc28 complex also has a role in transcriptional chromatin remodeling not related to kinase activity. In order to elucidate protein networks associated with Cks1 transcriptional functions, proteomic analysis was performed on immunoaffinity-purified Cks1, identifying a physical interaction with the Paf1 complex. Specifically, we found that the Paf1 complex component Rtf1 interacts directly with Cks1 and that this interaction is essential for efficient recruitment of Cks1 to chromatin in the context of GAL1 gene induction. We further found that Cks1 in this capacity serves as an adaptor allowing Rtf1 to recruit 19S proteasome particles, shown to be required for efficient RNA production from some rapidly inducible genes such as GAL1.
authors.affiliation: Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, California, USA.
authors.forename: Yen-Ru
authors.initials: YR
authors.lastname: Pan
authors.forename: Michael
authors.initials: M
authors.lastname: Sun
authors.forename: James
authors.initials: J
authors.lastname: Wohlschlegel
authors.forename: Steven I
authors.initials: SI
authors.lastname: Reed
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002843:Chromatin / Q000378:metabolism; D005686:Galactokinase / Q000235:genetics*; D015966:Gene Expression Regulation, Fungal; D056426:Genetic Loci; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D011485:Protein Binding; D020543:Proteome / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C081185:CKS1 protein, S cerevisiae; D018797:Cell Cycle Proteins; D002843:Chromatin; D009687:Nuclear Proteins; C097698:PAF1 protein, S cerevisiae; D020543:Proteome; D029701:Saccharomyces cerevisiae Proteins; C524219:GAL1 protein, S cerevisiae; D005686:Galactokinase; D046988:Proteasome Endopeptidase Complex